Modification of the surface of a base material with a particular molecular structure allows impartation of various properties to the base material or improvement of the properties of the base material. The impartation and improvement of properties are based on the interaction that the molecular structure introduced by modification has with other substances and, in some cases, on the form of the base material. Examples of the properties include separation medium property and adsorption property.
There are many known materials that have a surface over which hydrophilic groups are distributed. For example, glass, ceramic, and oxides such as silica and alumina generally have a surface covered by hydrophilic groups such as hydroxy groups. Thus, modification of the surface of a base material composed of such a substance can be accomplished by introducing a molecular structure using as a foothold the hydrophilic groups present on the surface. For surface modification of such a base material, a silicon compound may be used. It is common to use a halosilane such as chlorosilane or an alkoxysilane as the silicon compound. The silicon compound may be a so-called silane coupling agent having two or more different functional groups per molecule.
Meanwhile, Patent Literature 1 describes a process for coating a metal surface, the process including applying a reagent containing a reactive group selected from Si—H, Sn—H, and Ge—H in the presence of a platinum-group metal as a compound or in metallic form.